How do you clean up an html file?
For example, this file has one too many empty line between the div tags. I would like cleanup to leave only one blank line there.
<html>
<body>
<div>
foo
</div>
<div>
abc
</div>
</body>
</html>
What I tried in my emacs prelude
M-x help
d PATTERN Show a list of functions, variables, and other items whose
documentation matches the PATTERN (a list of words or a regexp).
entered 'clean html'
Nothing found
You can just use query-regexp-replace (bound by default to C-M-%)
to substitute three or more consecutive newlines with two newlines.
You need to know how to add a newline to your query and replacement
strings: C-q C-j. Altogether you'd type:
C-M-% C-q C-j \{3,\} RET C-q C-j C-q C-j RET !
(defun just-one-empty-line (&optional beg end)
"Delete consecutive empty lines, retain just one.
Works on region if active.
Accepts optional arguments BEG END to specify a region"
(interactive "*")
(let ((beg (cond (beg)
((region-active-p)
(region-beginning))
(t (point-min))))
(end (cond (end (copy-marker end))
((region-active-p)
(copy-marker (region-end)))
(t (copy-marker (point-max))))))
(save-excursion
(save-restriction
(narrow-to-region beg end)
(goto-char beg)
(while (not (eobp))
(while (looking-at "^\\([ \t]*\n\\)[ \t]*$")
(delete-region (match-beginning 1) (match-end 1)))
(forward-line 1))
(widen)))))
(emacs) Blank Lines, particularly about the commanddelete-blank-lines, which is globally bound toC-x C-oby default.